The present invention relates to a fiber material usable as a reinforcing and/or stiffening material for organic binders and inorganic binders as used in the construction industry, the binders including air-setting binders as well as hydraulic binders, as well as to a process for manufacturing such materials.
In view of the carcinogenity of asbestos fibers, it is an urgent requirement to find a substitute for this fiber. Asbestos, however, has certain well defined properties which are of value for use with inorganic and organic binders and which can be realized with other fiber materials only with difficulty. Since a substitute product must possess the same or at least approximately the same properties and fiber prices play a significant part, the possibilities for solving this problem are rather limited.
Lignified vegetable fibers, wood fibers and cellulose fibers are the only raw materials which replenish themselves and which, in the long run, are available as substitutes. The elastomechanical and physical characteristics of these fibers are also most likely those which would permit their use as a substitute for asbestos fibers.
According to analysis made in the asbestos industry, such a substitute must meet the following requirements: "It must be heat resistant, flexible, spinnable, noncombustible, have insulating properties, can easily be bound in numerous inorganic and organic binders and, depending on its type and species, should have a certain stability." Moreover, a substitute for chrysotile asbestos must be able to bind with cement. Prior attempts to provide such a substitute based on cellulose and glass fibers have not been successful because they resulted in fibers which did not have sufficient strength.